External source won't record on iPhone

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Level 1

25 points

External source won't record on iPhone

Even though I have used an adapter to connect an external "line level" source (an iPad) to a TRRS plug, I can't record on my iPhone. The adapter is routing the signal to the Sleeve of the plug, but I can only record via the internal iPhone mic.

Apparently there is a setting to switch from the internal mic to the input jack that I'm not adjusting correctly, but I can't find it. Turning off access to the (internal) microphone doesn't work, either.

Ideas?

Dick

iPhone 6

Posted on Jan 16, 2019 2:54 PM

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Answer 1

DHuitema Author

Level 1

25 points

Jan 25, 2019 5:34 AM in response to DHuitema

I have found my own answer!

The typical adapter that connects a (condenser) mic and a pair of earphones, or a headset to an iPhone or other "smart" device's 4-pin jack won't do it. They don't have a path for direct current that smart devices use to sense them. As a result those adapters won't cause an iPhone to switch from the internal mic to whatever is connected to the jack. Standard condenser mics or headsets do have a path for DC, so they work. That means connecting a Aux output or earphone jack to an iPhone requires an adapter that not only puts the signal on the "sleeve" of the 4-pin plug (nearest the handle), it must also have a resister connected from the signal lead to the common lead.

The Headset Buddy Mic Line-Level 3.5mm Audio Input Adapter Cable ($22) and the iRig 2 ($30) do that. The iRig 2 does lots more, too. Both are sold by Amazon.

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